octave: Sparse Functions

 
 22.1.4.1 Sparse Functions
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 Many Octave functions have been overloaded to work with either sparse or
 full matrices.  There is no difference in calling convention when using
 an overloaded function with a sparse matrix, however, there is also no
 access to potentially sparse-specific features.  At any time the sparse
 matrix specific version of a function can be used by explicitly calling
 its function name.
 
    The table below lists all of the sparse functions of Octave.  Note
 that the names of the specific sparse forms of the functions are
 typically the same as the general versions with a “sp” prefix.  In the
 table below, and in the rest of this article, the specific sparse
 versions of functions are used.
 
 Generate sparse matrices:
      “spalloc”, “spdiags”, “speye”, “sprand”, “sprandn”, “sprandsym”
 
 Sparse matrix conversion:
      “full”, “sparse”, “spconvert”
 
 Manipulate sparse matrices
      “issparse”, “nnz”, “nonzeros”, “nzmax”, “spfun”, “spones”, “spy”
 
 Graph Theory:
      “etree”, “etreeplot”, “gplot”, “treeplot”
 
 Sparse matrix reordering:
      “amd”, “ccolamd”, “colamd”, “colperm”, “csymamd”, “dmperm”,
      “symamd”, “randperm”, “symrcm”
 
 Linear algebra:
      “condest”, “eigs”, “matrix_type”, “normest”, “normest1”, “sprank”,
      “spaugment”, “svds”
 
 Iterative techniques:
      “ichol”, “ilu”, “pcg”, “pcr”
 
 Miscellaneous:
      “spparms”, “symbfact”, “spstats”
 
    In addition all of the standard Octave mapper functions (i.e., basic
 math functions that take a single argument) such as “abs”, etc.  can
 accept sparse matrices.  The reader is referred to the documentation
 supplied with these functions within Octave itself for further details.